High-heeled boots for bubs kicked by critics

The 42-year-old singer cancelled two concerts in Canada and the US after getting "suddenly ill during the sound check" in Montreal, according to a statement from W and W Public Relations.

She was taken to hospital and later released. No further details have been given about Jackson`s condition, but the singer is said to be planning to reschedule the performance.

Michael Wielgus, a spokesperson for promoter Gillett Entertainment Group, who organised the concert, added: "We`re not entirely sure what happened. We don`t have all the details."

People magazine reports Jackson had recently complained of exhaustion, according to a source.

"A 42-year-old body can`t handle what a 22-year-old body can," said the source, People reports.

"I can tell you that she`s definitely tired. It was probably exhaustion. She is doing back-to-back, three-hour shows, and her body isn`t the same as it used to be."

This is the second time this year the star has received hospital treatment.

In March Jackson checked into the Los Angeles` Cedar-Sinai Medical Center to be treated for flu symptoms after complaining of "shortness of breath".

At the time Jackson`s representative released a statement explaining: "Janet is fine. She is just battling this flu like everyone else."

Jackson is currently on a North American tour to promote her new album Discipline.